1. Field of the Invention
The instant invention relates to adhesives, composite articles containing adhesives, and processes of making the same. More particularly, the instant invention relates to an adhesive composition comprising a thermosetting powder adhesive adhered to a two-stage thermoplastic non-woven web adhesive, composite articles containing said adhesive, and processes of making the same.
2. Prior Art Description
Cloth and/or vinyl coverings are used in a number of industries, notably the automotive industry, as protective and decorative outer surface materials. For example, internal automotive parts including seats, dashboards, and door panels are generally covered with a cloth and/or vinyl covering. However, the covering is not naturally adherent to the metal, plastic, rubber and/or wood application surfaces. Therefore, an intermediate layer of adhesive is used to bind the covering to the application surfaces.
A wide variety of adhesives have been employed as the intermediate binding layer. These adhesives include thermoplastic powders, films, webs, and hot melt adhesives, as well as thermosetting water based and solvent based liquid adhesives. Unfortunately, every adhesive employed to date comes with its own unique set of problems. For example, thermoplastic powders, films, webs and hot melts must be applied in accordance with very restrictive time and temperature parameters and yield poor heat resistance. In addition, liquid adhesives require the use of bulky and expensive spraying equipment, and related cleaning and overspray disposal systems, for effective application.
More importantly, many of the adhesives employed to date exhibit premature bond failure. After several years the bond formed by the adhesive fails. This causes the covering to peel and results in an unsightly product that must either be patched or replaced. In the automotive industry this is a huge problem because the average life span of a car generally exceeds the life span of the adhesive. There is, therefore, a great need in the automotive art for a commercially viable adhesive that exhibits superior bond strength.
Such an adhesive would have use in any art wherein two incompatible materials need to be bonded. For example, such an adhesive could be used in combination with stiching to connect two portions of a cloth garment.